server.js

var express = require('express'),
    request = require('request'),
    bodyParser = require('body-parser'),
    app = express(),

    appId = process.env.APP_ID;

console.log(appId);

app.use(bodyParser.json());
app.use(express.static(__dirname + '/client'));


app.get('/appid', function(req, res) {
    res.send({appId: appId});
});

app.all('*', function (req, res, next) {

        var targetURL = req.header('Target-URL');
        if (!targetURL) {
            res.send(500, { error: 'There is no Target-Endpoint header in the request' });
            return;
        }
        request({ url: targetURL + req.url, method: req.method, json: req.body, headers: {'Authorization': req.header('Authorization')} },
            function (error, response, body) {
                if (error) {
                    console.error('error: ' + response.statusCode)
                }
            }).pipe(res);
});

app.set('port', process.env.PORT || 8200);

app.listen(app.get('port'), function () {
    console.log('Proxy server listening on port ' + app.get('port'));
});